3 taps x, y and z can fill a tank in 40 hours, 15 hours and 20 hours respectively. the three taps are turned on at 8.00a. m when the tank is empty for five hours then z is turned off. after two hours tap y is turned off. work out ;- the proportion of water in the tank after seven hours
the proportion of water in the tank after seven hours
the time the tank will be completely full

One integer is 8 times another. if the product is 72, then find the integers

It is given that the quadratic equation hx²-3x+k=0, where h and k are constants, has roots [tex] \beta \: and \: 2 \beta [/tex]express h in terms of k

Atravel agent is booking a trip to england, scotland, ireland, and france for a group of senior citizens. the agent sent surveys to the group, asking which countries they would like to visit, in order, and created the shown preference schedule (e = england, i = ireland, s = scotland, f = france). which country is the condorcet winner? number of votes 15 12 16 19 1st f e e i 2nd e s i s 3rd s i s e 4th i f f f 1. scotland 2. england 3. france 4.ireland